Page 125 - Big Ideas Year 10 sciPAD 2025

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© Silverback Academic Media 125
SCIPAD - BIG IDEAS - BOOK 2
FORCES AND MOTION
Forces and Acceleration
When unbalanced forces act on an object, the object will accelerate. If the object’s mass and its
rate of acceleration is measured, the amount of force acting can be calculated:
Fnet = ma
Fnet
=
net force (N)
m
=
mass (kg)
a
=
acceleration (ms-2)
A Worked Example
1. An object with a mass of 4.0 kg accelerates at 2 ms-2.
Calculate the net
force acting on the object. Fnet = ma
= 4 kg x 2 ms-2
= 8 N
1. Use words to describe the following units. The first one has been for you.
(a) kg: kilogram
(b) N: 
(c) m s-2:

2. Calculate the force acting on the following objects.
(a) A ball (m = 0.5 kg) accelerates at 1 m s-2
when it is thrown.



(b) An projectile with a mass of 2 kg is shot from a catapult. It accelerates at 200 m s-2­.



(c) A 10 kg mass is pushed horizontally and accelerates at 5 m s-2
.



(d) A 2.5 kg mass falls and accelerates at 10 m s-2
.



3. A motorbike, a car and a bus all accelerate at the same rate.
(a) Suggest which vehicle’s engine will have to generate the most force.

(b) Justify your answer to (a). 


You should ALWAYS
show
•
formula
•
working
•
answer
•
units
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